Signors to schering-xahi



Patented Mar. 26, 1929.

UNITED STATES PATENT OFFICE.

MAX DOHRN SIGNORS TO SCHERING-KAHLIBAUM AKTIENGESELLSGHAFT.

METHOD OF PRODUCING PYBIIDINE DERIVATIVES.

No Drawing. Application filed February 23, 1928, Serial No. 256,474, and in Germany March 31, 1927.

Emample 1.

Into a solution of Q-pyridone in chloroform chlorine gas is introduced. After removal of the chloroform by distillation a crystalline mass is obtained which consists of a mixture of 2-oxy-5-chloropyridine and 2-oxy-3.5-ehloropyridine OH N which can be separated by means of benzene.

Ewwmple grams 2-pyridone are dissolved in ccms. dilute hydrochloric acid and to the solution is added a solution of grams iodine mono chloride in dilute hydrochloric acid. After several hours standing at room 35 temperature the 2-oxy-3.5-iodine pyridine i on N separates out in pure state.

Various changes may be made in the details disclosed in the foregoing specification without departing from the invention or sacrificing the advantages thereof.

In the claims the term Q-pyridone is intended to include also the derivatives of this compound.

'We claim 1. The process of producing halogen-substituted Q-pyridone comprising dissolving the 2-pyridone in suitable solvents and halogenating the dissolved compound.

2. The process of producing iodine-substituted 2-pyrid0ne comprising dissolving Q-pyridone in a suitable solvent and iodizing the dissolved compound. 7

3. The process of producing 2-oxy-3.5- iodo pyridine comprising dissolving El-pyridone in dilute hydrochloric acid and adding iodine mono chloride.

In testimony whereof we affix our signatures.

' MAX DOHRN.

RALPH DIRKSEN. 

